The present invention relates to a process for removing the alkali metal hydroxide contaminants from alkali metal alkoxide in alcohol solutions by treatment with carboxylic acid esters.
Solutions containing alkali metal alkoxides and the corresponding alcohols are almost always contaminated with varying amounts of alkali metal hydroxides. These contaminants are generally formed as by-products in the preparation of alkali metal alkoxide solutions due to the presence of water in the alcohol employed and are additionally formed during the storage and handling of such solutions as a result of their absorption of water. Contamination of alkali metal alkoxide solutions by alkali metal hydroxides is, however, an important problem in that these contaminants reduce the yield of products prepared in processes using the solutions as a reagent and cause the formation of by-products which must be removed. The result is a higher cost of production and additional waste that must be disposed of.
There is currently no good way to remove alkali metal hydroxide contaminants from solutions containing alkali metal alkoxides and the corresponding alcohol. The general approach to the problem has been to try to avoid their formation in the preparation, storage, and use of such solutions.